Global Patent Index - EP 0514816 A1

EP 0514816 A1 19921125 - Dynamic lead screw engagement and indicator.

Title (en)

Dynamic lead screw engagement and indicator.

Title (de)

Dynamische Einrückung für Verschiebungsspindel mit Einrastanzeige.

Title (fr)

Engagement dynamique d'un vis-ecrou avec détection d'engagement.

Publication

EP 0514816 A1 19921125 (EN)

Application

EP 92108366 A 19920518

Priority

US 70433791 A 19910523

Abstract (en)

Automatic engagement of a lead screw (42) with a lead screw drive mechanism (44). A plunger driver (20) used to move the plunger (24) of a syringe (18) is connected to the screw drive mechanism. A first detector (38) provides a plunger signal indicating the presence of a syringe plunger in the plunger driver and a second detector (60) provides a thread engagement signal indicating engagement or disengagement of the lead screw drive mechanism with the lead screw. The thread engagement detector monitors movement of a rigid linkage at the screw drive mechanism which has a nonlinear characteristic curve. In the case where the plunger signal indicates the presence of a plunger and the thread engagement signal indicates engagement of the drive mechanism with the lead screw, the lead screw is rotated in a forward direction to remove the thread clearance. In the case where the thread engagement signal indicates disengagement of the drive mechanism with the lead screw, the processor rotates the lead screw first in a reverse direction and then in a forward direction to cause engagement of the threads. <IMAGE> <IMAGE>

IPC 1-7

A61M 5/145; F16H 25/20

IPC 8 full level

A61M 5/145 (2006.01); F16H 25/20 (2006.01)

CPC (source: EP US)

A61M 5/1456 (2013.01 - EP US); F16H 25/2025 (2013.01 - EP US); A61M 2005/14573 (2013.01 - EP US); Y10S 128/01 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

US 5106375 A 19920421; DE 69215270 D1 19970102; DE 69215270 T2 19970522; EP 0514816 A1 19921125; EP 0514816 B1 19961120

DOCDB simple family (application)

US 70433791 A 19910523; DE 69215270 T 19920518; EP 92108366 A 19920518